Mo1257 NITROUS OXIDE CRYOBALLOON ABLATION IS A SAFE, EFFECTIVE AND DURABLE ENDOSCOPIC TREATMENT FOR DYSPLASTIC TREATMENT-NAÏVE AND PREVIOUSLY-ABLATED BARRETT’S ESOPHAGUS

Abstract

Nitrous oxide cryoballoon (CB) ablation can effectively and safely eradicate dysplasia and intestinal metaplasia (IM) in patients with dysplastic BE but the durability of treatment effect is unknown. We evaluated the safety, efficacy, and durability of CB ablation for complete eradication of dysplasia and IM. We analyzed the outcomes of consecutive BE patients treated with CB at a single academic medical center for dysplastic BE from 2015 to 2018. We excluded patients with invasive adenocarcinoma, those treated primarily with radiofrequency ablation (RFA), and those enrolled in ongoing clinical trials. CB ablation was applied to all the gastric cardia and all visible BE using the CB focal ablation system and default cryogen dose of 10 seconds, after eradication of neoplastic-type lesions with endoscopic mucosal resection (EMR). “Touch-up” ablation was performed using CB or argon plasma coagulation for small residual columnar islands. Primary endpoints were complete eradication of dysplasia (CE-D) and intestinal metaplasia (CE-IM) at 1, 2, 3, 4 years. Secondary endpoints were adverse events, disease progression, recurrence rate, time to recurrence, treatment success after recurrence. Patients who achieved CE-IM were included for the durability analysis. Kaplan-Meir analysis was performed to assess durability where any recurrence was considered a failure. 70 patients (mean age 67.6 years, 88.6% male, mean BE Prague C 2.5+/- 4.3 cm, Prague M 4.3 +/- 4.6 cm), HGD=64%, LGD 36%) were studied. 65.7% of the patients were treatment naïve, the rest had prior EMR (n=6), RFA (n=13) or both (n=5). Median follow-up was 27.4 months (IQR 16.1-43.4). CE-D and CE-IM at 1 year were 96.7% and 73.8%, respectively. The median number of CB sessions to achieve CE-IM at 1 year was 3 (IQR 2-3.5). Table 1 shows the rates of CE-D and CE-IM for years 1-4, allowing for re-treatment with CB or “touch-up” APC. The rate of CE-IM was above 90% at 2, 3 and 4 years, with no difference between treatment-naïve and previously-ablated The durability (rates of CE-D and CE-IM) of CB response in 45 patients who achieved CE-D or CE-IM at 1 year followed until last follow-up or recurrence of dysplasia or IM are presented in Figure 1. One patient had an LGD recurrence at 21.7 months and 3(4.3%) patients had a recurrence of IM; all were successfully re-treated with CB ablation. The median time to recurrence was 18.6 months (Figure 1). No patient progressed beyond their baseline dysplasia grade or developed cancer. The incidence of stricture requiring dilation was 7.1%. 1 patient (1.4 %) developed self-limited bleeding. Recurrence rate of IM after initial CB eradication is low. CB ablation has high efficacy, safety, and durability for eradicating dysplasia and intestinal metaplasia in dysplastic BE as a primary or rescue therapy.Figure 1Kaplan-Meier analysis of the durability of complete eradication of dysplasia and intestinal metaplasia. All subjects in this analysis achieved either complete eradication of dysplasia (n=58) or intestinal metaplasia (n=45) at 12 months. Time 0 for this analysis is the first finding of complete eradication of dysplasia or intestinal metaplasia at 12 months. Any recurrent dysplasia (n=1 LGD) or IM (n=3; 2 HGD, 1 LGD) noted after achieving CE-D or CE-IM was considered a failure, even if it was subsequently successfully eradicated by cryoballoon ablation.View Large Image Figure ViewerDownload Hi-res image Download (PPT)